Cable guiding means for material handling apparatus



Jan. 7, 1947. I w, Ru oc I 2,413,786

CABLE GUIDING MEANS FOR MATERIAL HANDLING APPARATUS Filed Oct. 18, 19432 Sheets-Sheet 1 7 +4 INVENTOR. ML/AMEUDDGCM,

ATTORN EY.-

Jan. 7, 1947. w, D K 2,413,786

CABLE GUIDING MEANS FOR MATERIAL HANDL ING APPARATUS Filed Oct. 18, 1943'2 Sheets-Sheet 2 INVENTCR. ,WJLL/AM .Euooocz,

ATTORNEY.

Patented Jan. 7, 1947 CABLE-GUIDIN G MEANS FOR 'MATERIAL HANDLINGAPPARATUS Williamltuddock, South Pasadena Calif assignor, by direct andmesne assignments, to The 'McOaffrey Ruddock Tagline Corporation, LosiA-ngelesgfialii, a corporation of California Application October .18,1943, Serial No. 506,668

This invention relates to cable tensioning apparatus; more particularlythe invention relates to means for maintaining a cable or line free fromslack, and contemplatesan improved fair lead for guiding the cable tosuch means.

In various types of hoisting equipment, such as those utilizing a bucketfor handling material. it is common to attach a line or cable to thebucket to steady the bucket and prevent its rotating as it hangs by itshoisting cable, due to the tendency of the hoisting cable to untwist, orto other causes. For such a line to be efiective, and to preventexcessive slack therein as the bucket is raised or lowered, means aregenerally provided to maintain the line under tension and to vary theeffective length of the line in accordance with the position of thebucket so that the line is maintained under substantiallyconsta-nttension. One method of appropriately tensioning such a lineis by theprovision of a rotatable drum having spring means continuously urging itto rotate in one direction and upon which the line is wound so as towind on the drum or unwind therefrom in response to movement of thebucket. Such an arrangement is shown in my patents, Number 2,166,4'29and Number 2,303,902, issued July 18, 1939, and Novemberfie, 1942,respectively.

It is an object of this invention to provide novel means for guidingsuch a line to the tensioning means.

' It is another object of this invention to provide such guide meanswhich may be readily adjusted to accommodate various directions ofapproach of the line to the tensioning means.

It is another object of this invention to provide such guide meansadapted to be mount-ed in the plane of a drum for accommodating cable orline and arranged for angular adjust ment about the axis of the drum. s

It is still another object of this invention to provide such guide meansincorporating a pair of curved surfaces between which the line passes,whereby a large variation in the angle at which the line enters theguide means may be accom modated, at the same time the angle throughwhich the line is bent by the guide means kept small.

It is a still further object of this invention to provide a novel formof angul'arly adjustable clamping means.

This invention possesses many other advantages and has other objectswhich may be made more easily apparent from a consideration of oneembodiment of'the invention. For this purpose thereis "shown a'form inthe drawings accompanying 2 Claims. (Cl. 254 -190) 2 and forming part ofthe present specification. This form will now be described in detail,illustrating the general. principles of the invention; but it is to beunderstood that this detailed description is not to be taken in alimiting sense, since the scope of the invention is best defined by theappended claims.

In the drawings:

Figure 1 is an elevation showing the invention in use;

Figure 2 is a'fragmentary elevation on an enlarged scale as seen fromline 2-2 of.Figure 1;

Figure 3 is a section taken on line 3'--I-l of Figure 2;

Figure 4 is a section on a further enlarged scale taken on line 3-4 ofFigure 3;

Figure 5 is a fragmentary section taken on line 5-5 of Figure 4;

Figure 6 is a section taken on line t6 of Figure 5; and,

Figure '7 isan elevation as seen from line 1-1 of Figure 5.

Referring to Figure 1 of the drawings, the boom of a conventionalhoisting apparatus is indicated by l and is shown by way of illustrationas supporting, by means of a cable 2, a materia i handling bucket 3. Asis well understood, the boom l is arranged to be swung about its lowerend l to adjust the position of the bucket 3, and the bucket is alsoarranged to be raised and lowered with respect to the boom by meansofth'e cable- 2. To steady the bucket 3 and prevent its swinging androtating with respect to the-boom, a line or cable 5 is attached to thebucket 3 and extends to the boom, where means ii are provided formaintaining the line under appropriate tension and preventing slackeningthereof for any position of the bucket.

,The tensioning means 6 as shown in Figures 2, 3 and 4, includes a drum1 for accommodating the cable 5,.the drum i being rotatably mounted onsupporting means 3 which is apropriately secured on the boom I. Meansare provided for exerting a force continuously urging the drum 7 to Frotatein a direction to wind the cable 5 thereon,

drum-land the bucket 3 is generally indicated by ill; -andcomprisesmeans forming a pair of opposed curved surfaces II and I2 carried by aframe I5. The surfaces II and I2 are curved in the plane of the drum Iand may be conveniently provided by sheave wheels I3 and I4 rotatablymounted on the frame l5. The guide means In is mounted in the plane ofthe drum I, being supported for adjustment about the axis of the drum,to accommodate different directions of approach of the cable to thedrum.

As clearly indicated in Figure l, the cable 5 moves through a largeangle with respect to the guide means It as the bucket 3 is raised andlowered, such movement causing the cable to move out of contact with oneof said surfaces II or I2 and into contact with the other surface. Thus,with the bucket 3 in the full line position, the cable 5 passes over thesurface If on its way to the drum I and is clear of the surface I2 (seealso Figures 3 and 5). Similarly, as the bucket 3 is lowered, the cable5' remains in contact with the surface II, the angle of contactincreasing. As the bucket 3 is raised, the cable 5 will move out ofengagement with the surface I I and pass about a portion of the surfaceI2 on its way to the drum i, as indicated by broken lines, Figures 1, 3and 5.

Brief consideration will show that by providing a pair of surfaces IIand I2 as described, the angle through which the cable 5 is bent as itis guided to the drum I is materially reduced for a given movement ofthe bucket 3, since the total required angle is divided between the twosurfaces. To take full advantage of this fact, it is necessary that theposition of guide means It] be angularly adjustable about the axis ofthe drum I. In this way the angular movement of the cable may besubstantially equally divided between the two surfaces. For this purposethe frame I5 is supported and arranged for angular movement about theaxis of the drum I. Thus, the support 8 for the drum I can beconveniently used for supporting the frame i5, the frame I5 beingpositioned to appropriately guide the cable 5 to the drum. For thispurpose, the frame I5 has a pair of arms I5 and II which mayconveniently be angle irons, secured thereto as by welding. As bestshown in Figures 2 and 3, the arms I 6 and I1 extend from the frame I5to the drum support 8, being suitably inclined, or provided with anoffset, to position the sheaves I3 and I4 in alignment with, or in theplane of, the drum I and arranged to straddle the support 8.

The support 8 as shown comprises a cylindrical member I8, or at least isprovided with a cylindrical surface on that portion which is between thearm I6 and II, the cylindrical surface being coaxial with the drum I.For engaging the cylindrical surface of the member I8, each arm I6, IIhas a short length of channel-shaped bar 2|], 2| secured theretoextending axially of the member I8. These channels 20 and 2| are peferably of such proportions and size with respect to the diameter'ofthe cylindrical surface that the ends of the legs 22 of the channelsengage the cylindrical surface, the web 23 being clear of the surface.In this way, by forcing the arms I6 and II with the channels 23 and 2|together and into engagement with the cylindrical surface, the structureii! is effectively secured to the support 3. For urging the arms I8 andI1 together, bolts it are provided which extend through the arms I6 andIf on opposite sides of the member I8.-

It' will be apparent that by loosening the bolts 24 the structure ii)may be moved angularly about the drum I, whereby the sheaves I3 and I4maybe positioned to properlyguide the line 5 to the drum. Tightening ofthe bolts serves to clamp the arms I6 and I1 together with the structureII) in adjusted position. Thus, the support 8 can be mounted in anyposition, the structure Ill being adjusted accordingly.

Since the drum I and the surfaces II and I2 are in the plane of movementof the bucket 3, there is little tendency for the cable 5 to movelaterally of the drum I. To guide the cable in such direction, the frameI5 is arranged to provide a narrow passage for the cable over the curvedsurfaces I I and I2, as indicated in Figures 6 and 7. To prevent rapidwear of the frame I5 by the cable 5 as it passes through the framebetween the bucket 3, and the drum I, the outer end of the opening inthe frame I5 is provided with a liner 25 having a long narrow opening 21for accommodating the cable. Theexterior of the liner 25 is adapted toengage theinterior surface of the frame I5, a lip 28 on the liner 25engaging the lower edg of the frame I5. Cap screws 29 passing throughthe opposite sides of the frame I5 thread into lugs 30 on the liner 25,and serve to retain the liner in the frame I5. It will be plain thatremoval of the cap screws 29 will permit the liner 25 to be detachedfrom the frame l5, after which a new liner may be installed and securedby replacement of the screws 29.

The support 8 for the drum I will now be briefly described, referencebeing had particularly to Figures 2 and 4. Therein it will be seen thatthe tubular member I8 has a mounting pad secured to it near one endthereof for cooperating with a member 35 of the derrick boom I, the pad35 being clamped to the member by bolts 31 and a plate washer 38. Theopposite end of the tubular member I8 rests on the member 39 on theother side of the boom I, being secured thereto by a U-bolt 40 passinover the member I8 and engaging a plate washer 4i beneath a cross member42 joining the boom members 36 and 39. Th s method of attachment permitsthe tensioning means 6 to be readily installed in any position on aderrick boom or other existing equipment without the need of drillingholes or altering the boom or equipment in any Way. Furthermore, thetensioning means can be shifted easily to a different operating positionshould this seem desirable, or the entire structure can be reversed soas to place the drum I on the opposite side of the boom I, the guidemeans I0 being angularly adjusted to properly position the guide sheavesI3 and I4.

The end of the member I8 adjacent the pad 35 is closed by a detachablehead 44 having a hub 45 forming a bearing for the shaft 46, to the outerend portion of which the drum I is secured. The inner end portion of theshaft 46 has one end of an inner drum 41 secured thereto,

the opposite end of the drum 4'! having a bushing 48 fixed therein whichis rotatably supported on a stationary stub shaft 49 formed on a head 58closing the end of the member I8. A helical spring 5I surrounds the drum41, being secured at one end 52 to the head 44 and at its other end 53to th bushing 48 and hence to the drum 41.

It will be apparent that the spring 5! will urge the drum I to rotateso. as to take up any slack in the line 5;' further it will resilientlyopflimoving the bolts securing the head 44in place,

and rotating the head 44 to tighten or loosen the spring 5| as required.

I claim:

1. In a fair lead for use with a rotatable drum positioned beyond oneend of a supporting structure, said structure providing a cylindrica1surface extending entirely about the axis of said drum, means forguiding a line with respect to the drum, comprising means forming a pairof opposed convex surfaces providing a space through which the line isadapted to pass, and a frame secured at one endto said guide means,com-- prisin a pair of spaced arms adapted to straddle said cylindricalsurface, each of said arms having a pair of projectingelements at theopposite end from the guide means adapted to engage said surface atangularly spaced areas thereon of limited angular but substantial axialextent, and means for causing said arms to clamp said elements to saidsurface to secure said guide means with said convex surfaces in a planenormal to the drum axis and with said space in adjusted angular positionabout the drum axis.

2. In a fair lead for use with a rotatable drum positioned beyond oneend of a supporting structure, said structure providing a cylindricalsurface extending entirely about the axis of said drum, means forguiding a line with respect to the drum, comprising means forming a pairof opposed convex surfaces providing a space through which the line isadapted to pass, and a frame secured at one end to said guide means,comprising a pair of spaced arms adapted to straddle said cylindricalsurface, each of said arms having a pair of projecting elements at theopposite end from the guide means adapted to engage said surface atangularly spaced areas thereon of limited angular but substantial axialextent, said frame having a length greater than the radius of the drumand being directed toward the drum, and means for causing said arms toclamp said projecting elements to said surface, the axial length of saidelements serving in connection with the cylindrical surface to positionsaid guide means at a point spaced beyond the periphery of the drumintermediate the ends of the drum, and with said convex surfaces curvingin a plane normal to said drum axis.

WILLIAM RUDDOCK.

